Method for printing colored and white toner using a device link profile

ABSTRACT

A method for printing on a receiver with a plurality of colored dry inks including dry black ink and a dry white ink, the method includes the steps of providing a set of multidimensional look-up tables for transforming a set of color channel inputs to a set of colored channel outputs; inputting a set of color values to the multidimensional look-up table, which values corresponds to a color rendition at each pixel location of the receiver; wherein the multidimensional look-up table outputs a new set of laydown values corresponding to the input channels and a white laydown at each pixel location; and printing the laydown values at each pixel location with the plurality of colored dry inks and dry white ink.

CROSS REFERENCE TO RELATED APPLICATIONS

Reference is made to commonly assigned U.S. patent application Ser. No.______ (Docket No. K001571/PCW) concurrently filed by Chung-Hui Kuo,entitled “Method For Printing Colored And White Toner Using A Look-UpTable”, and commonly assigned U.S. patent application Ser. No. ______(Docket No. K001904/PCW) concurrently filed by Chung-Hui Kuo, entitled“An Apparatus For Printing Colored And White Toner”.

FIELD OF THE INVENTION

The present invention generally relates to electrophotographic printersand, more particularly, to electrophotographic printers that deposit“dry” white ink (commonly referred to as white toner) in a controlledamount for cost efficiencies and image quality.

BACKGROUND OF THE INVENTION

Electrophotographic printers produce images by depositing toner onreceivers (or “imaging substrates”), such as pieces or sheets of paperor other planar media, glass, fabric, metal, or other objects. Printerstypically operate using subtractive color: a substantially reflectivereceiver is over-coated image-wise with cyan (C), magenta (M), yellow(Y), black (K), and other colorants. Other toner compositions can alsobe used to produce effects beyond simple image appearance.

In electrophotography, there is a need to deposit white toner incombination with colored toner for various purposes such as imagequality and the like. The prior art discussed below deposits white inkand other color toner on the receiver.

For example, U.S. Patent Publication 2009/0220695 A1 discloses a methodof creating a record medium using an ink jet process by which anon-white background can be completely hidden. This is achieved byprinting a metallic ink first and then a white pink. Wherever there isan overlap between the two layers, an opaque layer is formed whichcompletely hides the background color or transparency of the medium. Acombination of metallic and white layers creates the opaque layer whichis extremely white because of the scattering by the white layer andreflecting properties of the metallic layer.

U.S. Patent Publication 2011/0234660 A1 discloses a method of printingon a transparent medium by IJ process using color inks, metallic ink andwhite ink. The opaque areas are created by the process described in the'695 disclosure above. Use of white and metallic provides the costadvantage as well as be able to provide the desired luster effects. Theimage is viewed from the non-printed side for transparent substratewhere the white layer is uniformly applied farthest from the medium.From opaque medium, white is applied first and then metallic and finallythe color inks are jetted. The metallic layer serves as a specialtygloss layer to provide different effects and opacity.

U.S. Patent Publication 2013/0145383 A1 discloses an inkjet recordingmethod which uses a white overlaying layer. The process is designed forremote proofing in which a longitudinal film is passed through twoseparate IJ stations. The substrate may contain an ink reception layer.

If the substrate is opaque, white is first laid down uniformly and afterwhite layer is dried, color image is applied above it and dried again.On the other hand, when the substrate is transparent, color image isapplied first and then dried. This is followed by the uniformapplication of white inkjet drops over the entire color image areaswhich are then dried again. In another variation, the white can beapplied on the opposite surface in the case of a transparent substrate.Because the white is inkjet based, the preferred pigments are hollow orporous to avoid settling of heavy titania based white pigment. Itfurther discloses an “inverse” type white ink application [0054 and0057]; however, the white usage is based on total amount allowed by thesubstrate.

Although satisfactory, in U.S. Patent Publication 2009/0220695 A1, thereis no adjustment of the white laydown with respect to the subsequentcolor inks, and two layers or more layers are required to create thisopaque image. In U.S. Patent Publication 2011/0234660 A1, which is aninkjet process, there is no control of white ink based on color inkdensity; white is printed farthest from the viewing side, behind colors,not alongside. In U.S. Patent Publication 2013/0145383 A1, two printingstations are used, not one printing station, and the total white amountcan exceed the total non-white amount ink. The present inventionincludes the advantages of adjusting the white laydown relative to colortoner layers which reduces total toner cost, preserves the possiblespecial visual effect provided by specialized substrates such asmetallic/pearlescent substrate, and optimizes printable color gamut.

SUMMARY OF THE INVENTION

The present invention is directed to overcoming one or more of theproblems set forth above. Briefly summarized, according to one aspect ofthe invention, the invention resides in a method for printing on areceiver with a plurality of colored dry inks including dry black inkand a dry white ink, the method comprising the steps of providing a setof multidimensional look-up tables for transforming a set of colorchannel inputs to a set of colored channel outputs; inputting a set ofcolor values to the multidimensional look-up table, which valuescorresponds to a color rendition at each pixel location of the receiver;wherein the multidimensional look-up table outputs a new set of laydownvalues corresponding to the input channels and a white laydown at eachpixel location; and printing the laydown values at each pixel locationwith the plurality of colored dry inks and dry white ink.

These and other objects, features, and advantages of the presentinvention will become apparent to those skilled in the art upon areading of the following detailed description when taken in conjunctionwith the drawings wherein there is shown and described an illustrativeembodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features, and advantages of the presentinvention will become more apparent when taken in conjunction with thefollowing description and drawings wherein identical reference numeralshave been used, where possible, to designate identical features that arecommon to the figures, and wherein:

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter of the present invention, itis believed that the invention will be better understood from thefollowing description when taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is an electrophotographic printer useful for implementing thepresent invention;

FIG. 2 is a block diagram illustrating details of the logic and controlunit and its interaction with printing modules of the present invention;

FIG. 3 is an alternative embodiment of the logic and control unit andits interaction with printing modules of the present invention;

FIG. 4 is a third embodiment of the logic and control unit and itsinteraction with printing modules of the present invention; and

FIG. 5 is a fourth embodiment of the logic and control unit and itsinteraction with printing modules of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Before discussing the present invention, it is useful to understand theterm “dry ink” as used herein. In this regard, dry ink refers to tonerparticles deposited on a substrate which are later fixed to thesubstrate by pressure, heat or both. In contrast, liquid ink refers toinkjet processes where liquid ink is deposited which then dries forforming an image on a substrate.

In the following description, some embodiments will be described interms that would ordinarily be implemented as software programs. Thoseskilled in the art will readily recognize that the equivalent of suchsoftware can also be constructed in hardware. Because image manipulationalgorithms and systems are well known, the present description will bedirected in particular to algorithms and systems forming part of, orcooperating more directly with, embodiments described herein. Otheraspects of such algorithms and systems, and hardware or software forproducing and otherwise processing the image signals involved therewith,not specifically shown or described herein, are selected from suchsystems, algorithms, components, and elements known in the art. Giventhe system as described herein, software not specifically shown,suggested, or described herein that is useful for implementation of theinvention is conventional and within the ordinary skill in such arts.

FIG. 1 is an elevational cross-section illustrating portions of atypical electrophotographic printer 100 useful with various embodiments.Printer 100 is adapted to produce print images, such as single-color(monochrome), CMYK, CMYKF (five-color), or with the addition of a 6^(th)development station (which is not shown) hexachrome images, on areceiver (multicolor images are also known as “multi-component” images).Images can include either or a combination of text, graphics, photos,and other types of visual content. One embodiment involves printingusing an electrophotographic print engine having six sets ofsingle-color image-producing or printing stations or modules arranged intandem, but more or fewer than six colors can be combined to form aprint image on a given receiver. Other electrophotographic writers orprinter apparatus can also be included. Various components of theprinter 100 are shown as rollers; other configurations are alsopossible, such as configurations having belts.

The printer 100 is an electrophotographic printing apparatus having anumber of tandemly arranged electrophotographic image-forming printingmodules 31, 32, 33, 34, 35, also known as electrophotographic imagingsubsystems. Each printing module 31, 32, 33, 34, 35 produces asingle-color toner image for transfer using a respective transfersubsystem 50 (for simplicity and clarity, only one is labeled) to areceiver 42 successively moved through the modules. The receiver 42 istransported from a supply unit 40, which can include active feedingsubsystems as known in the art, into the printer 100. In variousembodiments, the visible image can be transferred directly from animaging roller to the receiver 42, or from an imaging roller to one ormore transfer roller(s) or belt(s) in sequence in transfer subsystem 50,and then to the receiver 42. The receiver 42 is, for example, a selectedsection of a web of, or a cut sheet of, planar media such as paper ortransparency film.

Each printing module 31, 32, 33, 34, 35 includes various components. Forclarity, these are only shown in the printing module 32. Aroundphotoreceptor 25 are arranged, ordered by the direction of rotation ofphotoreceptor 25, a charger 21, an exposure subsystem 22, and toningstation 23.

In the EP process, an electrostatic latent image is formed onphotoreceptor 25 by uniformly charging photoreceptor 25 and thendischarging selected areas of the uniform charge to yield anelectrostatic charge pattern corresponding to the desired image (a“latent image”). The charger 21 produces a uniform electrostatic chargeon photoreceptor 25 or its surface. The exposure subsystem 22selectively image-wise discharges photoreceptor 25 to produce a latentimage. The exposure subsystem 22 can include a laser and raster opticalscanner (ROS), one or more LEDs, or a linear LED array.

After the latent image is formed, charged toner particles are broughtinto the vicinity of the photoreceptor 25 by the toning station 23 andare attracted to the latent image to develop the latent image into avisible image. Note that the visible image may not be visible to thenaked eye depending on the composition of the toner particles (forexample clear toner). The toning station 23 can also be referred to as adevelopment station. The toner can be applied to either the charged ordischarged parts of the latent image. The toner particles can have arange of diameters, for example less than 8 micrometer, on the order of10-15 micrometer, up to approximately 30 micrometer, or larger(“diameter” refers to the volume-weighted median diameter, as determinedby a device such as a Coulter Multisizer).

After the latent image is developed into a visible image onphotoreceptor 25, a suitable receiver 42 is brought into juxtapositionwith the visible image. In the transfer subsystem 50, a suitableelectric field is applied to transfer the toner particles of the visibleimage to the receiver 42 to form the desired print image 38 on thereceiver 42, as shown on receiver 42A. The imaging process is typicallyrepeated many times with reusable photoreceptors 25.

The receiver 42A is then removed from its operative association withphotoreceptor 25 and subjected to heat or pressure to permanently fix(“fuse”) print image 38 to receiver 42A. Plural print images areoverlaid on one receiver before fusing to form a multi-color print image38 on the receiver 42A.

Each receiver 42, during a single pass through the six printing modules31, 32, 33, 34, 35, can have transferred in registration thereto up tofive single-color toner images to form an image. In one embodiment,printing module 31 forms black (K) print images, 32 forms yellow (Y)print images, 33 forms magenta (M) print images, 34 forms cyan (C) printimages and 35 forms white (W) print images. The receiver 42A is shownafter passing through the printing module 36. The print image 38 onreceiver 42A includes unfused toner particles.

Subsequent to transfer of the respective print images 38, overlaid inregistration, one from each of the respective printing modules 31, 32,33, 34, 35, the receiver 42A is advanced to a fuser 60, i.e. a fusing orfixing assembly, to fuse the print image 38 to receiver 42A. A transportweb 81 transports the print-image-carrying receivers (e.g., 42A) to thefuser 60, which fixes the toner particles to the respective receivers42A by the application of heat and pressure. The receivers 42A areserially de-tacked from transport web 81 to permit them to feed cleanlyinto fuser 60. The transport web 81 is then reconditioned for reuse atcleaning station 86 by cleaning and neutralizing the charges on theopposed surfaces of the transport web 81. A mechanical cleaning station(not shown) for scraping or vacuuming toner off the transport web 81 canalso be used independently or with cleaning station 86. The mechanicalcleaning station can be disposed along the transport web 81 before orafter the cleaning station 86 in the direction of rotation of thetransport web 81.

The fuser 60 includes a heated fusing roller 62 and an opposing pressureroller 64 that form a fusing nip 66 therebetween. In one embodiment, thefuser 60 also includes a release fluid application substation 68 thatapplies release fluid, e.g. silicone oil, to fusing roller 62.Alternatively, wax-containing toner can be used without applying releasefluid to the fusing roller 62. Other embodiments of fusers, both contactand non-contact, can be employed. For example, solvent fixing usessolvents to soften the toner particles so they bond with the receiver42. Photoflash fusing uses short bursts of high-frequencyelectromagnetic radiation (e.g. ultraviolet light) to melt the toner.Radiant fixing uses lower-frequency electromagnetic radiation (e.g.infrared light) to more slowly melt the toner. Microwave fixing useselectromagnetic radiation in the microwave range to heat the receivers(primarily), thereby causing the toner particles to melt by heatconduction, so that the toner is fixed to the receiver 42.

The receivers (e.g., receiver 42B) carrying the fused image (e.g., fusedimage 39) are transported in a series from the fuser 60 along a patheither to a remote output tray 69, or for duplex printing, back to theprinting modules 31, 32, 33, 34, 35 to create an image on the backsideof the receiver (e.g., receiver 42B), i.e. to form a duplex print.Receivers (e.g., receiver 42B) can also be transported to any suitableoutput accessory. For example, an auxiliary fuser or glossing assemblycan provide a clear-toner overcoat. Printer 100 can also includemultiple fusers 60 to support applications such as overprinting, asknown in the art.

In various embodiments, between the fuser 60 and the output tray 69, thereceiver 42B passes through the finisher 70. Finisher 70 performsvarious media-handling operations, such as folding, stapling,saddle-stitching, collating, and binding.

The printer 100 includes the main printer apparatus logic and controlunit (LCU) 99, which receives input signals from the various sensorsassociated with the printer 100 and sends control signals to thecomponents of the printer 100. The LCU 99 can include a microprocessorincorporating suitable look-up tables and control software executable bythe LCU 99. It can also include a field-programmable gate array (FPGA),programmable logic device (PLD), microcontroller, or other digitalcontrol system. The LCU 99 can include memory for storing controlsoftware and data. Sensors associated with the fusing assembly provideappropriate signals to the LCU 99. In response to the sensors, the LCU99 issues command and control signals that adjust the heat or pressurewithin fusing nip 66 and other operating parameters of fuser 60 forreceivers. This permits the printer 100 to print on receivers of variousthicknesses and surface finishes, such as glossy or matte.

Image data for writing by the printer 100 can be processed by a rasterimage processor (RIP; not shown), which can include a color separationscreen generator or generators. The output of the RIP can be stored inframe or line buffers for transmission of the color separation printdata to each of the respective LED writers, e.g. for black (K), yellow(Y), magenta (M), cyan (C), and white (W), respectively. The RIP orcolor separation screen generator can be a part of printer 100 or remotetherefrom. Image data processed by the RIP can be obtained from a colordocument scanner or a digital camera or produced by a computer or from amemory or network which typically includes image data representing acontinuous image that needs to be reprocessed into halftone image datain order to be adequately represented by the printer. The RIP canperform image processing processes, e.g. color correction, in order toobtain the desired color print. Color image data is separated into therespective colors and converted by the RIP to halftone dot image data inthe respective color using matrices, which comprise desired screenangles (measured counterclockwise from rightward, the +X direction) andscreen rulings. The RIP can be a suitably-programmed computer or logicdevice and is adapted to employ stored or computed matrices andtemplates for processing separated color image data into rendered imagedata in the form of halftone information suitable for printing. Thesematrices can include a screen pattern memory (SPM).

Further details regarding printer 100 are provided in U.S. Pat. No.6,608,641, issued on Aug. 19, 2003, to Peter S. Alexandrovich et al.,and in U.S. Publication No. 20060133870, published on Jun. 22, 2006, byYee S. Ng et al., the disclosures of which are incorporated herein byreference.

Referring to FIG. 2, there is shown in block diagram details of theportion of the LCU 99 for rendering white toner based on the amount ofcolored toner being rendered. The LCU 99 receives images files, such as,but not limited to, RGB, CMYK, pdf, raster or vector files, that aresent to a CMYK rendering engine 102 which converts the particular imagefile into a standard CMYK format and then separates the CYMK format fileinto individual color components—Cyan component, Magenta component,Yellow component, and Black component. These individual color componentsare then each sent to either a one-dimensional transform 105 a or aone-dimensional look-up table (LUT) 105 b. The transform 105 a or LUT105 b takes the particular color component and obtains the correspondingwhite laydown at each pixel location. It is noted that the white colorcomponent varies according to the amount of the particular colorcomponent as illustrated schematically in FIG. 2. The LUT 105 b is in atable format in which corresponding values are stored; transform 105 ais a real-time look-up in which an algorithm determines thecorresponding white laydown; and look-up table as used herein refers toeither embodiment. The basic algorithm is to deposit maximal amount ofwhite toner on the area of the media corresponding to the white point ofthe image, and gradually reducing monotonically the amount of whitetoner laydown relative to each increasing color toner laydown. The rateof white toner laydown reduction is dependent on the opacity of eachcolor toner, the intended substrate's background color, and the tonerlaydown sequence. For example, the black toner has very high opacity. Asa result, the white toner reduction rate relative to the black toner canbe higher than other color toners such as yellow. Furthermore, thebackground color of the intended substrate will also affect the whitetoner reduction rate relative to each color toner laydown. For example,if the substrate is metallic, since the substrate surface is veryreflective, the purpose of the white toner is simply to sufficientlyblock the underlying metallic texture structure without losing themetallic appearance. The white toner reduction rate will be much higherthan that on a colored card board substrate. The four 1-D transforms orLUTs (105 a or 105 b), one for each colorant, each output a value forthe white laydown (W1, W2, W3, W4). Those values are input to acomputational engine 110 that determines the print value for each pixellocation based on the white laydown values from each transform or LUT(105 a or 105 b).

The determined value for W could be simply the smallest of the set ofwhite values (W1, W2, W3, W4), or it could be an overage of the set ofwhite values (W1, W2, W3, W4), or it could even be the largest of theset of white values (W1, W2, W3, W4). The value for the white inklaydown W and the original values for the colorants (CMYK) are providedto the printing module 31-15 for rendering and physical lay down andfinishing of the colorants on the receiver.

Referring to FIG. 3, there is shown an alternative embodiment forrendering white toner based on the amount of colored toner beingrendered. The LCU 99 receives images files, such as, but not limited to,RGB, CMYK, pdf, raster or vector files, that are sent to the CMYKrendering engine 102 which converts the received image file into astandard CMYK format and then separates the CYMK format file intoindividual color components—C component, M component, Y component, and Kcomponent. The CMY values are combined in an effective laydown engine120 to determine an effective laydown of the colorants and then theeffective laydown is sent to either the one dimensional transform 105 aor the one dimensional LUT 105 b, which is used to determine the desiredlaydown of white ink W5 at each pixel location (the y values) dependingon the effective laydown of the colored inks (CMY). The opaque blackvalue K is provided to either a separate one dimensional transform 105 cor one dimensional LUT 105 d which correlates the laydown of the blackink (K) to another white laydown W6 based on the black ink. In otherwords, the two 1-D transforms or LUTs (either 105 a or 105 b and either105 c or 105 d), one for the effective CMY and one for the black Klaydown, each output a value for the white laydown (W5, W6). The W5 andW6 values are input to the computational engine 110 that determines theprint value for each pixel location based on the white laydown valuesfrom each transform or LUT (either 105 a or 105 b and either 105 c or105 d). To determine the effective laydown of the colored ink (CMY),first treat each distinct color toner as the same type of toner. Withina unit area, then compute the percent of averaged coverage of this newtoner where the overlapped area of two of more color toner is countedonly once. This averaged coverage can also change with respect to thehalftone screen structure.

The determined value for W in this embodiment could be simply thesmallest of the set of white values (W5, W6), or it could be an overageof the set of white values (W5, W6), or it could even be the largest ofthe set of white values (W5, W6). The value for the white ink laydown Wand the original values for the colorants (CMYK) are provided to theprint engine modules 31-35 for rendering and physical lay down andfinishing of the colorants on the receiver.

Referring to FIG. 4, there is shown a third embodiment for renderingwhite toner based on the amount of colored toner being rendered. The LCU99 receives images files, such as, but not limited to, RGB, CMYK, pdf,raster or vector files, that are sent to a CMYK rendering engine 102which converts the received image file into a standard CMYK format andthen separates the CYMK format file into individual color components—Ccomponent, M component, Y component, and K component. The CMYK valuesare combined in an effective laydown engine 120 to determine aneffective laydown of the colorants and black and then the effectivelaydown is sent to either the one dimensional LUT 105 a or 105 b, whichis used to determine the desired laydown of white ink W7 at each pixellocation (the y values) depending on the effective laydown of thecolored inks and black dry ink (CMYK). The 1-D transform or LUT (105 aor 105 b) outputs a value for the white laydown (W7). That valuedetermines the white ink print value for each pixel location based onthe effective laydown of CMYK. The value for the white ink laydown W7and the original values for the colorants (CMYK) are provided to theprinting module 31-35 for rendering and physical lay down and finishingof the colorants on the receiver.

Referring to FIG. 5, there is shown a fourth embodiment for renderingwhite toner based on the amount of colored toner being rendered. The LCU99 receives images files, such as, but not limited to, RGB, CMYK, pdf,raster or vector files, that are sent to a CMYK rendering engine 102which converts the received image file into a standard CMYK format andthen separates the CYMK format file into individual color components—Ccomponent, M component, Y component, and K component. The CMYK valuesare then combined using a color profile known as the Device Link Profile130 to determine the desired laydown of all the dry inks, C′M′Y′K′ andW′. The effective laydowns are provided to the printing modules 31-35for rendering and physical lay down and finishing of the colorants onthe receiver. The advantage of utilizing a Device link profile toprovide proper white toner laydown relative to the color toner laydown,such as C,M,Y,K, and possibly other supplemental accent color toners,from the digital controller is its capability to specify differentamount of white toner laydown at different color toner laydowncomposition on the intended printing substrate. A printer output devicelink profile is composed of a multidimensional LUT from N-color inputchannels to M-Color output channels. In the case of creating a separatewhite toner layer, the dimension of the input/output color channels is Nand N+1 respectively. In one embodiment, each color toner is assignedwith its own opacity coefficient ranging from 0 to 1, where 0 meanscomplete transparent and 1 means complete opaque. For example, theopacity coefficient for yellow toner is usually set as the lowest amongall color toners and the black toner is usually set to be 1. Based on achosen halftone screen set for every color channel, the effectivesubstrate-blocking ratio, Br, on a unit area by all color toner laydowncombined in the multidimensional LUT of the Device link profile can becomputed. The white toner laydown, W′, is inversely correlated with thecomputed substrate-blocking ratio, for example, W=1−Br. This correlationfunction will also be dependent on the selected substrate. At the sametime, C′M′Y′K′ are computed taking into account grey component removaland the type of substrate used.

Grey component removal is used by the Device link profile to substitutea quantity of black ink for the grey component of the CMY inks. TheDevice link profile uses properties of the receiver to determine themultidimensional look-up table transforms, and properties of thereceiver include the color of the receiver, type of the receiver orreflectance of the receiver. The Device link profile also depends onorder of laydown of the colored, black and white toner on the receiver.

The present invention has been described in detail with particularreference to certain preferred embodiments thereof, but it will beunderstood that variations and modifications can be effected within thespirit and scope of the invention.

PARTS LIST

-   21 charger-   22 exposure subsystem-   23 toning station-   25 photoreceptor-   31 printing module-   32 printing module-   33 printing module-   34 printing module-   35 printing module-   38 print image-   39 fused image-   40 supply unit-   42 receiver-   42A receiver-   42B receiver-   50 transfer subsystem-   60 fuser-   62 fusing roller-   64 pressure roller-   66 fusing nip-   68 release fluid application substation-   69 output tray-   70 finisher-   81 transport web-   86 cleaning station-   99 logic and control unit (LCU)-   100 printer-   102 CMYK rendering engine-   105 a transform-   105 b one-dimensional look-up table (LUT)-   105 c transform-   105 d one dimensional look-up table (LUT)-   110 computational engine-   120 effective laydown engine-   130 Device link profile

1. A method for printing on a receiver with a plurality of colored dryinks including dry black ink and a dry white ink, the method comprisingthe steps of: determining a laydown amount of color inks and black inkat each pixel by computing an input value at each pixel location from aninput file; providing a look-up table having a set of one dimensionallook-up tables for each of the colored inks and black ink, wherein thelook-up table receives a colorant value corresponding to a laydown ofthe color inks and the black ink at each corresponding pixel location ofthe receiver; wherein the look-up table determines a laydown of whiteink at each pixel location depending on the laydown of the colored inksand black ink; and printing the laydown of white ink, color inks andblack ink with the plurality of colored dry inks and dry white ink. 2.The method as in claim 1 further comprising using opacity of the coloredinks to determine the set of one dimensional look-up table transforms.3. The method as in claim 1 further comprising using desired level ofgrey component removal of the colored inks to determine the set of onedimensional look-up table transforms.
 4. The method as in claim 1further comprising using properties of the receiver to determine the setof one dimensional look-up table transforms.
 5. The method as in claim4, wherein the properties include the color of the receiver, type of thereceiver or reflectance of the receiver.
 6. The method as in claim 1,wherein the one dimensional look-up table transform depends on order oflaydown of the colored, black and white ink on the receiver.
 7. A methodfor printing on a receiver with a plurality of colored dry inksincluding dry black ink and a dry white ink, the method comprising thesteps of: providing a set of multidimensional look-up tables fortransforming a set of color channel inputs to a set of colored channeloutputs; inputting a set of color values to the multidimensional look-uptable, which values corresponds to a color rendition at each pixellocation of the receiver; wherein the multidimensional look-up tableoutputs a new set of laydown values corresponding to the input channelsand a white laydown at each pixel location; printing the laydown valuesat each pixel location with the plurality of colored dry inks and drywhite ink; and using desired level of grey component removal of thecolored inks to determine the multidimensional look-up table transforms.